Re: tickle nmi watchdog whilst doing serial writes.

From: Arjan van de Ven
Date: Fri May 13 2005 - 14:35:04 EST


On Fri, 2005-05-13 at 14:48 -0400, Dave Jones wrote:
> if (up->port.flags & UPF_CONS_FLOW) {
> tmout = 1000000;
> while (--tmout &&
> - ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
> + ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0)) {
> udelay(1);
> + touch_nmi_watchdog();
> + }
> }
> }
>
>
> We *could* tickle it less often, but given we're busy waiting anyway
> it probably doesnt make sense to not favour the more simple approach.
> Hmm, maybe we want a cpu_relax() in there too. opinions?

udelay() includes cpu_relax() already so that is futile.

However.. this is a hack. Do we really need to do busy waiting here for
this long??


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